IN-VIVO STUDY OF A CALCIUM-PHOSPHATE CEMENT CONSISTING OF ALPHA-TRICALCIUM PHOSPHATE DICALCIUM PHOSPHATE DIBASIC/TETRACALCIUM PHOSPHATE MONOXIDE/

Prehardened calcium phosphate cement consisting of alpha-tricalcium ph osphate (alpha-TCP), dicalcium phosphate dibasic (DCPD) and tetracalci um phosphate monoxide (TeCP) was implanted in rabbit mandibles and bac k muscles, and studied histologically and microradiographically. In th e mandibles, new bone formation occurred around the implants and incre ased in quantity the longer the implant period lasted. Histology, micr oradiography and scanning electron microscopy (SEM) demonstrated direc t contact of bone and cement. Bone response to this cement was essenti ally the same as to hydroxyapatite (HA) ceramics, known as a biocompat ible bone substitute. Material resorption was recognized, which increa sed with the implant period and was greater in the surface bound by so ft tissue than the surface bound by bone tissue. In the back muscles, however, no calcified tissue formation occurred. Resorption proved to be faster than in the case of the mandible implants. It was concluded that the cement, in prehardened form, has good biocompatibility and is a promising material as a bone substitute. (C) 1996 Elsevier Science Limited.